Horticulture lighting is the method for promoting plant growth by artificial lighting fixtures when natural light is lacking.
Professional horticulture lighting is not just about providing sufficient light for plant growth through the enhancement of photosynthesis, but also about helping plants to produce a more beautiful flower, better shape of leaves and more fruit as well as reduce or lengthen a specific growing phase.
For professional horticulture lighting, the right customized recipes are essential for optimization of plant growing on purpose. The specific needs of various plants in each growing phase and each part of plant organs determine which lighting recipe is better for optimize growth.
Growth
Aside from the variables consisting of temperature, humidity, water, oxygen, carbon and nutrients, special qualities of lighting also play an important part in controlling plant growth. The light intensity, spectrum and duration affect plants' morphology, growth, fruiting and flowering.
Photosynthesis
Plants can convert light energy into chemical energy by photosynthesis. Plants need to absorb special light spectra emitting in order to generate essential elements, such as chlorophyll, anthocyanin, carotenoid and phytochromes, within its organs for growing. A professional horticulture lighting recipe must optimize the spectrum of light source to fulfill the plants needs for photosynthesis in order to increase the growth speed and limit the electrical energy consumption at the same time.
PAR: Photosynthetically Active Radiation
Photosynthetically active radiation, also called PAR, stands for the spectral range of solar radiation from 400nm to 700nm. It defines the light the plant needs to sustain photosynthesis. In this range, plants' photosynthetic organisms have the ability to absorb light in the process of photosynthesis.
PPF: Photosynthetic Photon Flux
Photosynthetic photon flux (PPF) is a measurement that establishes the overall amount of photosynthetic active radiation (PAR) a light produces. It values all photons from 400nm to 700nm based on the plant's photosynthetic response.
PPFD: Photosynthetic Photon Flux Density
Photosynthetic photon flux density (PPFD) is an additional measurement that offers the same information as PPF. It also stands for the photons in the spectral range of 400nm to 700nm. While the difference between them is that PPF measures how many photons are given off from a light source. On the other hand, PPFD is about how many photons drop on a surface area in square meters.